BONNIFIELD AND KANTJSHNA REGIONS. 210 
I Stibnite (antimony sulphide) occurs in the wash of Caribou Creek, 
lid a ledge containing this mineral has been located a short distance 
Ibove the point where the creek emerges from the hills into the 
enched area of the lower valley. The creek forks at this locality, and 
r the southern fork, which has been named Last Chance, the ledge is 
scposed. The vein is about 4 feet thick, and the vein matter includes 
jsentially quartz and stibnite. The quartz is partly massive and 
artly in the form of small crystals up to an inch in length. The 
titimony sulpiride is in part a crystalline mass embedded in the spaces 
etween the quartz crystals and in part a bluish-black, very fine- 
rained massive variety. The ledge strikes northeastward and dips 
5° N. The country rock is hornblende schist, to the structure of 
hich the vein conforms. A short distance upstream the hornblende 
Bast is structurally conformable to the quart zi tic schist. A small 
mount of work was being done here in the hope that the ledge mate- 
al would be found to carry values. Of three specimens from this 
reality assayed for the Survey two contained silver at the rate of 4 
nd 2.76 ounces to the ton and the latter carried in addition 0.12 
unce of gold to the ton; the third specimen contained 0.12 ounce of 
old, but no silver. Too little work had been done to give definite 
Eiformation regarding the proportion of the antimony sulphide in the 
ein, but pieces of nearly solid ore up to a foot in diameter were 
btainable. 
SUMMARY. 
The Kantishna placers are in an area of crystalline schists. The 
^old-producing creeks head near each other. The bed rock of all 
4ie creeks comprises practically the same kinds of rock and the 
gravels are shallow. The bulk of the gold in every case has in all 
Drobability been derived from the valley in which it is found. The 
occurrence is not confined to any particular section of the valleys, 
but is such as to suggest a derivation from different points along 
them. The manner of its occurrence in the bed rock is indicated by 
the many pieces found in most intimate association with quartz, by 
a small flat nugget one-tenth of an inch thick attached to garnetif erous 
mica schist, and by the occurrence of silver- and gold-bearing galena 
and stibnite in the gravels of several creeks. Pieces of these sulphide 
ores a foot or more in diameter were observed in the gravels, and the 
fact that in one case high values in silver with some associated gold 
were carried by this material lends not only a qualitative interest 
to this occurrence but a quantitative one as well. The vein of stib- 
nite on Caribou Creek, although carrying in the material tested no 
high values in silver or gold, illustrates the form of occurrence, and 
its interest is enhanced from the fact that the metal antimony, which 
forms about 70 per cent of the mineral stibnite, is at present (1907) 
